Snoring
–
A new study finds evidence that at least one species of dinosaur may have been a skilled swimmer, diving into the water to duck to hunt prey.
A study published in Biology Communications on December 1 describes the newly discovered species, Polydontus natovenator. Theropod, or hollow dinosaur with three fingers and claws on each limb, lived in Mongolia during the late Cretaceous period, 145 to 66 million years ago.
Scientists from Seoul National University, the University of Alberta, and the Mongolian Academy of Sciences collaborated on the paper.
Researchers have shown that Natovenator had streamlined ribs like those of birds.
“The shape of its body suggests that Natovenator was a powerful swimming predator and that the most powerful body evolved independently among distinct theropod dinosaur genera,” the authors wrote.
The Natovenator specimen is very similar to Halszkaraptor, another dinosaur found in Mongolia that scientists believe was likely semi-aquatic. But the Natovenator specimen is more complete than the Halszkaraptor, which makes it easier for scientists to see the appearance of its most ugly body.
Both Natovenator and Halszkaraptor probably used their arms to propel themselves through the water, the researchers explained.
David Hone, a paleontologist and professor at Queen Mary University of London, told CNN it’s hard to say where Natovenator falls on the spectrum of all land-dwelling to all-aquatic. But the arms of the specimen “will be similar enough to move the water,” he said. He shared this peer review for his study of Communication Biology.
Additionally, Natovenator had dense bones, which are necessary for animals to swim under the surface of the water.
As the authors wrote, it had a “relative hydrodynamic body.”
The next step, Hone said, would be to model the dinosaur’s body to help scientists understand exactly how it might have moved. “Is it a peg for feet, a peg for a dog? How fast could he go?”
Further research should also look into the environment in which Natovenator lived. The specimen was found in Mongolia in the Gobi Desert, but it is clear that lakes and other bodies of water existed in the desert before.
“The real question is, OK, you’ve got a swimming dinosaur in the desert, what’s swimming?” he said. “Finding fossils of these lakes is very difficult, but sooner or later, we may well find them. And when we do, we may well find many of them.
Nizar Ibrahim, a senior lecturer in paleontology at the University of Portsmouth, whose research found that Spinosaurus was likely semiaquatic, told Rhode that he is not entirely convinced by the findings so far. He argued that a more detailed quantitative analysis would have made the findings more robust.
“I would like to see, for example, a solid description of bone density, the osteohistology of an animal, within a broader species profile,” he said. “Even the anatomy of the ribs, if they had a look at the bigger picture – a lot of data that would have been useful.”
“The anatomical records are less straightforward” for swimming Natovenator than it was for swimming Spinosaurus, he said.
And like Hone, he is also curious as to exactly what waters Natovenator could swim in. “This animal was found in the Mongolian environment, the exact opposite type of what you think of as an aquatic animal,” he said.
But he hopes the study could help open up more expansive ideas about dinosaur behavior. Dinosaurs were previously thought to be strictly terrestrial, but increasingly, evidence has emerged suggesting that at least some species spent as much time in water as on land.
“I’m sure there will be many, many more surprises,” said Ibrahim. “And we’re going to find that dinosaurs are not only around the longest, but also, you know, really different and very good at invading a new environment.”
#species #dinosaur #swooped #duck #catch #prey #Snoring
